Stroke-induced microRNAs: The potential therapeutic role for stroke.

Stroke is one of the leading causes of death and disability worldwide. In past decades, researchers have studied the physiopathology and biochemistry of stroke, but knowledge of the molecular mechanisms underlying this disease remains at an early stage. To date, only recombinant tissue plasminogen activator (rtPA) has been approved by the USA FDA for acute ischemic stroke. However, as the limiting therapy time window is 4.5 h after stroke onset and patients must meet the applicable conditions, a small number of patients benefit from this therapy. Therefore, the research and development of new drugs for stroke are a big challenge for scientists. MicroRNAs (miRNAs) are short (20-23 nucleotides) single-stranded non-coding RNAs. The seed sequences at positions 2-7 from the 5' end which are partially or complementary to one or more mRNAs inhibit or degrade target mRNAs, thus playing an important role in the post-transcriptional regulation of gene expression. Disregulated miRNAs have revealed their complex role in pathophysiological processes, and have also shown their potential role in disease diagnosis, and use as drug targets in neurodegenerative diseases and cancer. Recently, studies have found aberrantly expressed miRNAs in stroke; however, the implication of deregulated miRNA expression in stroke remains largely unknown. This review briefly summarizes recent studies concerning miRNA expression in stroke in vivo and in vitro, focuses on aberrant miRNA expression, as well as discusses their potential therapeutic role for stroke.